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DURING the late 40s the impetus given to air transport development by the war began to spread to some of the then more remote parts of the world. The lack of certain parallel developments on the ground became apparent, in particular the need for better communication facilities and air traffic control. War‐time necessities had led to the building up of satisfactory communications and an air traffic control system in Europe and parts of the Middle East, but the operational needs of airlines now had to be met outside these areas, for example in North Africa, Central Africa, and the area around the Arabian or Persian Gulf as it is variously called. This led to the formation of International Aeradio Ltd. in 1947.

Air traffic resources mainly include two parts, namely, air traffic controller (ATC) and physical system resources, such as airspace. Reasonable assessment and effective management of ATC and airspace resources are the premise and foundation of ensuring the safety and efficiency of air traffic management systems. The previous studies focussed on subjective workload control and the statistics of control communication time; they revealed the lack of kinetic universality analyses of controlling actions. Although frequency distribution patterns were generated by controlling the timing sequence, the correlation between the controlling actions and terminal airspace (TMA) sector capacity was not revealed. The paper aims to discuss these issues.

Thus, given the immeasurable complexity of controlling actions and statistical features of the controlling communications, a dynamical model of ATC was built in this study to identify the frequency distribution patterns generated by controlling the timing sequence. With the Directorate of Operational and Analysis Task method, TMA sector capacity was estimated through multiple linear regression analysis.

With data from the Kunming sector, the power exponent was calculated as 2.55, and the mathematical expectation was determined to be 47.21 s. The correlation between controlling actions (workload) and sector capacity was obtained. Finally, the data were integrated in the verification of the model and its feasibility.

Airspace capacity is an index to measure the ability of the airspace system to deliver services to meet the air traffic demand. A scientific and accurate forecast of airspace capacity is a foundation of the effective management and rational allocation of the airspace resources. The study is of great significance for the efficient use of airspace resources, controller resources.

This paper aims to identify methods of guidance and supervision used in air traffic control training. It also aims to show how these methods facilitate trainee participation in core work activities.

The paper applies the tools of conversation analysis and ethnomethodology to explore the ways in which trainers and trainees act and interact in training situations. The data consist of the video recordings (total 38 hours) and ethnographic material gathered at a vocational institute for aviation and in two aerodrome control tower units.

The trainers used five different instructional strategies with which they guided and controlled the trainees' actions. In simulator training, learning was structured as a process through which the procedural knowledge possessed by the expert controllers was transferred to the trainees through interventions such as orders, test questions and additions. As the trainees progressed to the on‐the‐job training phase, interaction evolved from being trainer‐driven to trainer‐guided. The trainees' performance was fine‐tuned and guided towards local practices of particular work position by means of instructions and information deliveries.

The simulator training and on‐the‐job training appear as two distinctive forms of vocational training with their own aims. In order to improve the quality of the training, it is suggested that greater attention should be given to the ways in which these two separate areas of learning could be better reconciled.

This ethnomethodological study on training interaction complements the understanding of instructional strategies used at different stages of air traffic control training. It is proposed that research into the local and social production of training interaction can shed useful light on the complexities of workplace learning and training interaction, providing a novel perspective for those engaged in practice of vocational education.

At a recent Convention held at the Royal Aeronautical Society, the topics of Current Problems and Future Concepts relating to Air Traffic Management were given extensive treatment by speakers from a variety of backgrounds. In his paper on ‘NATS — Taking Stock’, Air Commodore Huxley described the historical basis of the National Air Traffic Services and mentioned its formation some 20 years ago. At that time, the prospect was for a much more complicated mixture of civil and military aviation and an integrated solution had to be found. The three arbitrary areas of military, commercial and recreational flying each have to maintain their major fields of common interest and at the same time, avoid possible mutual conflicts. Thus, for example, reliable public transport aircraft require a close working relationship between the operator and the ATC system, whereas in military flying, the emphasis is on self‐reliance. Over the 20 years referred to, there has been a three‐fold increase in the volume of en‐route traffic and the altitude has been doubled at which most of it wishes to fly. In the future, the prospect of reducing separation is not considered very probable and among other possibilities, tighter control of low‐level flying is considered probable.

Modeling and system performance analysis play an important role in the planning of air traffic system. In particular, this paper aims to concentrate on the modeling and the performance evaluation of air transportation system.

It has shown that system matrices inherent in the airspace network can be acquired based on the service times of flights. This paper deals with a logical modeling which can avoid temporal synchronization conflict of resources. As a result, a class of queuing system is investigated to obtain a representation of the airspace network dynamics using dioid model.

The analysis of the air traffic system is conducted by solving the system state model. This indicates that it is feasible to use eigenvalues of system model for acquiring characteristics of the considered air transport systems.

The departure scheduling prototype presented in this paper can offer air traffic controller a decision support tool to build optimal departure sequences for aircraft.

The properties of max-plus algebra described allow us to apply linear algebra concepts like eigenvalue and eigenvectors to obtain a solution to the air traffic system being modeled. By solving and analyzing the dioid model, this paper evaluated some performance measures of airspace network.

NOT perhaps the most vintage of Farnboroughs from the point of view of new aircraft and new technology, but undoubtedly one of the most successful in relation to the business done. Some fifteen major orders worth over £32½ million were announced, bringing the total order book for the industry this year to more than £782 million already. This exceeds by a handsome margin the new business won by the industry in any nine‐month period in the past, and it is expected that by the end of the year orders worth well over £800 million will have been received. Highlights of the new British hardware on show were the Hawker Siddeley Nimrod and production Harriers on the military side; the B.A.C. One‐Eleven 500, the Handley Page Jetstream, the Garrett‐engined Short Skyvan, and the Beagle Pups showed the resurgence of the industry's civil interests. The number of foreign aircraft that appeared, sponsored in the main by Rolls‐Royce, bore witness to the strength of Britain's aero engine and aircraft equipment industry, and further evidence of this was found in the exhibition proper with many examples of major items of equipment having been adopted for overseas markets. The overall impression at Farnborough was a new‐found confidence in the future of the industry exemplified by a more aggressive and effective export sales policy that has already proved our ability to deliver the goods. It is not possible to cover all the exhibits shown at Farnborough, but the report following describes many of the interesting items.

TO say that the Twenty‐fourth S.B.A.C. Show was an unqualified success is perhaps to gild the lily. True there were disappointments— the delay which kept the TSR‐2 on the ground until well after the Show being one—but on the whole the British industry was well pleased with Farnborough week and if future sales could be related to the number of visitors then the order books would be full for many years to come. The total attendance at the Show was well over 400,000—this figure including just under 300,000 members of the public who paid to enter on the last three days of the Show. Those who argued in favour of allowing a two‐year interval between the 1962 Show and this one seem to be fully vindicated, for these attendance figures are an all‐time record. This augurs well for the future for it would appear that potential customers from overseas are still anxious to attend the Farnborough Show, while the public attendance figures indicate that Britain is still air‐minded to a very healthy degree. It is difficult to pick out any one feature or even one aircraft as being really outstanding at Farnborough, but certainly the range of rear‐engined civil jets (HS. 125, BAC One‐Eleven, Trident and VCIQ) served as a re‐minder that British aeronautical engineering prowess is without parallel, while the number of rotorcraft to be seen in the flying display empha‐sized the growing importance of the helicopter in both civil and military operations. As far as the value of Farnborough is concerned, it is certainly a most useful shop window for British aerospace products, and if few new orders are actually received at Farnborough, a very large number are announced— as our ’Orders and Contracts' column on page 332 bears witness. It is not possible to cover every exhibit displayed at the Farnborough Show but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

Most of the existing approaches for flight collision avoidance are concerned with local traffic alone for which the separation is based on the pairwise analysis of aircraft trajectory trends, which is not efficient with regard to some flight path requirements along waypoints. The purpose of this paper is to deal with the global collision avoidance problem which aims at separating aircraft taking into consideration the global traffic in a given area instead of considering them pairwise. It aims to model the concept of global collision avoidance and propose a validated algorithm for the purpose in the framework of free‐flight.

The collision avoidance procedure computes online the appropriate speed and heading for each aircraft, at each sampling time‐instant, to generate a collision‐free flight trajectory along scheduled waypoints. The method accounts for automatic assignment of priority indexes that are updated from one control time horizon to the next. The paper considers here the case of aircraft flying at the same altitude, but the proposed method is easily extendable to the general 3D situation. Owing to the predictive features that are inherent to collision avoidance, the collision‐free trajectories are generated using model predictive control approach. A simulation example is presented in the end and its results show the suitability of the proposed approach.

Since the model predictive control approach is used, the collision avoidance procedure is anticipative; therefore, the avoidance capability depends only on the prediction horizon rather than on the control horizon.

The computation of the trajectory guidance information (speed and heading) at each time‐step is fast, therefore the proposed method is well suited for online processing requirements in real world applications.

The paper provides a flexible modelling framework and a computationally effective algorithm, both based on model predictive control concepts, to cope with global collision avoidance for flight safety enhancement in the framework of free‐flight.

Accles & Pollock Ltd. of Oldbury, Worcestershire, a TI Steel Tube Division company, will be exhibiting a comprehensive range of precision steel tube and tubular products, including plain, annularly convoluted and thin wall tube, at Farnborough.